The invention relates to a device for controlling the sliding and lifting movements of a cover for a sliding and lifting vehicle roof having an input drive element and an output drive element, and a gear assembly with a planetary gear which functions between the input drive element and the output drive element. More particularly, to a device for such a roof wherein the gear assembly, during operation of the drive elements, starting from a predetermined gear position corresponding to a cover reference position, automatically changes its gearing ratio on the basis of the drive direction in such a way that, at equal input drive speeds, the lifting movement produced is slower than the sliding movement.
In a prior art device of this kind (German Pat. No. 34 33 600 corresponding to U.S. Pat. No. 4,657,594), a clutch is provided having an axially adjustable gear, rendering the planetary gear effective for the lifting movement while creating a direct connection between the input drive element and the output drive element for the sliding movement.
Further there is disclosed an apparatus for controlling the sliding and lifting movements of a roof cover, wherein a rotatable hub input element is in driving connection with a driving pinion output element for producing sliding of the cover, and wherein a reduction stage (which may be a planetary gear arrangement) is engaged by an axial shifting of a control gear for driving the driving pinion to produce a tilting movement at a transmission ratio that is reduced relative to that for the sliding movement.
It is also known from a prior development of the present inventors, that is described in German Offenlegungsschrift No. 35 45 869 and corresponding U.S. Pat. No. 4,659,140, to provide a dual epicyclic gear for driving the cover assembly of a vehicle roof. However, the gear disclosed there is a distributor gear having two output drive elements which are to be driven individually or jointly with different ratios. That is, through the use of a reversing mechanism, one output drive element produces a lifting or lowering movement or another output element produces sliding of a roof cover, or both output drive elements are simultaneously operated to produce both lifting and sliding movements, the lifting and lowering produced by one output element being reduced relative to the sliding movement produced by the other output element.